Radiation shielding container



@am R. J. SMITH, JR., ETAL 2,935,616

RADIATION SHIELDING CONTAINER 2 Sheets-Sheet 1 l 2 Sheets-Sheet 2 INV 7NTORS ATTORNEYS May 3, 1960 R. J. SMITH; JR., ETAL RADIATION SHIELDINGCONTAINER Filed Feb. 14, 1955 5. AddLQ@ @MJ .7 ,I ,-l y

RADIATIDN SHIELDING CONTAINER Richard J. Smith, Jr., Stamford, andArnold J. Baldwin, West Haven, Conn., assignors to Farrel-BirminghamCompany, Incorporated, Ansonia, Conn., a corporation of ConnecticutApplication February 14, 1955, Serial No. 487,788

3 Claims. (Cl. Z50-108) This invention relates to a shielding containerfor radioactive materials, and more particularly to a container in whichsuch materials may be shipped, stored or handled in any manner, andwherein they will be properly shielded so as -to protect a person orsurrounding material from the injurious effects of harmful rays whichmay emanate from the radioactive substances.

In handling radioactive materials, protection must be afforded those whoare handling the material and also to surrounding matter which may beaffected by radiation from the material. Such protection may be affordedin the form of containers in which the -radioactive material is placedor stored. These containers are of necessity somewhat heavy and bulky,and in many instances represent a major item of cost in the shipping ofradioactive substances from place to place.

It is well known that the rays emanating from such substances tend totravel in straight lines and, if the container is of a sectionalcharacter or provided with joints, it is important that it be sodesigned as to provide a discontinuous or irregular cleavage planebetween such joints so yas to prevent the harmful rays passing outwardlythrough these joints. Also as the container must of necessity besomewhat heavy and bulky, it is desirable to achieve reduction in sizeand weight as much as possible in the shipping and handling of suchsubstances so as to reduce the cost of shipping and handling and also toconserve valuable storage space as far as possible.

As the amount of the radioactive material to be handled may vary fromtime to time, it is desirable that the container be so made so that itssize may be varied in order that an excessively large container will nothave to be employed for a small amount of material or, in thealternative, that many sizes of containers will not have to lbe made inaccordance with the amount of material which is to be stored or handled.

To this end it is contemplated by our invention to provide a sectionalcontainer which will properly shield material contained therein andwhich is so constructed that any number of sections may be employed soas to vary the size and weight of the container by varying the principaldimension thereof.

One object of the present invention -is to provide a new and improvedshielding container for radioactive materials.

A further object of the invention is to provide a shielding containerfor radioactive materials of sectional form so that by employing apredetermined number of sections a container of the desired size may beprovided, which container will properly shield the material therein.

A still further object of the invention is to provide a shieldingcontainer of sectional form for radioactive substances, the sectionsbeing built up one upon another so that any predetermined number thereofmay be employed and the sections being so constructed and assembled thatregardless of the number used, the contained material will be properlyshielded.

2,935,616v Patented May 3, 1960 lCe To these and other ends theinvention consists in the novel features and combinations of parts to behereinafter described and claimed.

In the accompanying drawings:

Fig. 1 is a side elevational view of a shielding container embodying ourinvention;

Fig. 2 is a sectional view on line 2--2 of Fig. 1;

Fig. 3 is a top plan view of one of the intermediate sections of thecontainer;

Fig. 4 is a sectional view similar to Fig. 2 of a container of somewhatmodified form;

Fig. 5 is a side elevational view of a further modification;

Fig. 6 is a sectional view on line 6--6 of Fig. 5; and

Fig. 7 is a sectional view of still another modification.

To illustrate a preferred embodiment of our invention, we have shown inFig. 1 of the drawings a shielding container designated generally by thenumeral 10. This container, as will be hereinafter described, isprovided with lrelatively thick walls and may be made of any desiredmaterial, such as iron, steel, lead or concrete, or any combination ofthese materials or other material having suitable shieldingcharacteristics for the harmful rays which may emanate from theradioactive material stored within it.

As illustrated, this container is provided with a lower or base section11, intermediate sections 12 and an upper section 13. It will beunderstood that while usually a base section and an upper or top sectionwill be employed, as many intermediate sections may be provided as arenecessary to provide a container of suitable size for the amount ofmaterial to be stored, shipped or otherwise handled. The lower or basesection 11 may, if desired, be provided with suitable supporting legs14, and the upper section may be provided with eye members 15 by whichthe container may be handled.

As shown more especially in Fig. 2 the upper surface of the lowersection is discontinuous or stepped in that it is provided with asubstantially plane surface 16 adjacent its central portion, an inclinedannular surface 17 surrounding the area 16, and a peripheral annularsurface 18 which may be in a plane substantially pariallel to that ofthe surface 16. Such an element provides a break in the joint betweenthis lower section and the next upper section so that rays finding a wayinto this joint will not have a straight-line passage into the exteriorof the container. The bottom section is also provided with a socket ordepression 19 which does not extend to the lbottom of the section butwhich opens through the top thereof substantially at the center of thefarea 16. This socket or well provides for the insertion therein of acontainer 20 for the radioactive material to f be shielded. The bottomsection is also provided with threaded openings 21 which open throughthe portion 18 of the upper surface of this section in order to securethe next upper section thereto as will be later described.

The intermediate sections 12 (and it will be understood that as many ofthese as desired may be employed) are of similar form and thedescription of one will suffice. Each of these sections is preferably ofthe same outside dimensions as that of the lower section so as to fitneatly thereon and on each other. They are, as shown, of cylindricalform although they may be of any other shape desired. Both upper andlower surfaces of these sections are provided with discontinuouscleavage planes in that the surfaces are stepped or broken so that theydo not lie in the same plane to provide a straight-line path foremanated rays. These surfaces comprise an inner annular surface 23surrounding a central through opening 24 and a surrounding inclinedannular surface 25 which is in turn embraced by an annular plane surface26.

It will be seen that when both upper and lower surfaces of thelintermediate sections are so formed, one will fit snugly and closelyupon the other and the lower of such sections will fit snugly andclosely upon the upper surface of the base section 11 so as to provide abroken or discontinuous joint between each of the sections.

Each of these sections is provided with through openings 27 to receivescrews or the like 28, which screws in the lowermost of the intermediatesections will be threaded into the openings 21 previously referred to soas to secure this section to the bottom section. The intermediatesections are also provided with upwardly facing screw-threaded openings29 which, as shown, are formed in the annular portions 26 of suchsection to receive screws 30 extending through the next upperintermediate section or the screw 31 extending through the top section13 if it is the upper one of the intermediate sections. This providesfor the securement of the lowerrnost intermediate section to the bottomsection and also for the securement of a further intermediate section orthe top section in place regardless of the number of intermediatesections which may be employed.

The upper section is provided with lower stepped or broken surfacecomplementary to the upper surface of the uppermost intermediate sectionso that it will iit snugly thereon and provide a discontinuous cleavageplane therebetween. The top section may also be provided with throughopenings 32 for the reception of the screws 31 so that the top sectionmay be screwed in place as described.

The inner container or liner 20 may be formed of any suitable material,and this liner may be made in various lengths depending upon the numberof sections of the outer container which it is desired to employ. Thisliner may be provided with an upper annular flange 33 which is ttedbetween the top section and the next lower section.

It will be apparent that with the above construction a shipping orstorage container for radioactive materials is provided which is ofsectional form so that any desired size of container may be employed byvarying the vertical dimension thereof in that any number of sectionsmay be employed. If desired, the top section may be seated directly uponthe lower section or any number of intermediate sections employedbetween the upper and lower sections. In assembling the container, it isonly necessary to select the liner of proper length to be employeddepending upon the number of intermediate sections which are used. Thecontiguous surfaces of the sections are complementally formed so thatthey will iit closely together upon discontinuous cleavage plans so asto provide proper shielding of the radioactive material. Moreover, theupper and lower surfaces of the intermediate sections are of identicalform and are of a form complemental to the upper surface of the lowersection and the lower surface of the upper section to provide for theclose fitting of all of the parts.

In Fig. 4 of the drawings we have shown a similar container except thatthe cleavage planes between the sections are separated by a sharp stepor shoulder. In this form of our invention the upper and lower surfacesof the intermediate sections 35 are provided with an inner annular area36 surrounding the central opening 37 and an outer annular area 38, theareas 36 and 38 being separated by a shoulder 39, the wall of which isat substantially right angles to the arcas 36 and 38. It will, ofcourse, be understood that the lower surface of the upper section andupper surface of the lower section are complementally shaped. Thesections may be secured together by suitable screws as previouslydescribed in connection with the form of our invention shown in Figs. lto 3.

In Figs. and 6 of the drawing there is illustrated a further embodimentof our invention in which the container may be formed of lead or othermoldable shielding material. In this form of the invention the lowersection comprises an outer casing 40 which serves as a form forcontaining the lead lling 41. The central opening may be provided by acylindrical sleeve 42, and the upper surface may be dened by the member43 of a suitable metal. As shown, the upper surface of the lead portionof the casing covered by the material 43 is similar in shape to that ofthe sections shown in Fig. l. That is, this area comprises a centralannular portion 45 surrounding the sleeve 42, an annular frustoconicalor inclined surface 46, and an annular peripheral surface 47 in a planesubstantially parallel to that of the surface 45 so as to provide abroken joint between the upper surface of the bottom section and thenext upper section.

Secured to the wall 40 by welding or the like is a ring 48 so that anintermediate section may be secured to the lower section just describedby screws 49. Any number of intermediate sections may be used as before,and each of these intermediate sections comprises an outer casing 50surrounding the inner lead portion 5l, and brazed or Welded to the outermember 50 is the ring 52 which corresponds to the ring 48 previouslydescribed. The upper and lower surfaces of this intermediate section aresimilar in shape and shaped to complement the upper surface of the lowersection so that the parts may be nested as previously described andsecured by the screws 49, 49a and 49h.

The upper section, as shown in Fig. 6, comprises an outer form 53containing the lead lling 54, the lower surface of this section beingshaped to complement the upper surface of the intermediate sectionimmediately below it so as to break the joint between the sections. Aninner container 55 may be positioned within the sleeve sections 42, 42.aand 42h. It will be understood that the sections 42a and 42b aresections of the two intermediate sections shown.

The upper section may also be provided with blocks S6 within which maybe screwed the eyes 57 to enable the device to be readily handled.

In Fig. 7 we have shown a further modification of our invention which issimilar to that described with respect to Figs. 5 and 6 except that itis provided with discontinuous cleavage planes between the sections, theelements of which are in the form of a reverse curve shown at 60. Itwill be understood that any form of broken or discontinuous jointsbetween the sections may be employed that will prevent the ernanation ofrays through the joints between the sections in straight lines.

While we have shown and described some preferred embodiments of ourinvention, it will be understood that it is not to be limited to all ofthe details shown, but is capable of modification and variation withinthe spirit of the invention and within the scope of the claims.

What we claim is:

l. A shielding container for radioactive material, said containercomprising a lower section having a cavity therein closed at its lowerend but opening through the upper surface of the section, said sectionbeing provided with a centrally disposed frusto-conical projection atits upper surface surrounding said cavity, an intermediate sectionhaving a central recess of frusto-conical shape at its lower surface tosnugly receive the frusto-conical projection on the lower section whenthe intermediate section is superposed thereon, said intermediatesection having a centrally disposed frusto-conical projection at itsupper surface of the same dimensions as the recess at its lower surface,and a central opening extending entirely through the section to registerwith the cavity opening in the lower section, and an upper sectionhaving, in its lower surface a centrally disposed recess offrustoconical shape and of the same dimensions as the recess in thelower surface of the intermediate section to snugly receive thefrusto-conical projection on the upper surface of said intermediatesection, the upper section having a solid portion to close the upper endof the opening in the intermediate section, and means for securing lallof said sections together, all of said sections being of radioactiveshielding material.

2. A shielding container as `in claim 1 wherein a plurality ofintermediate sections of the `identical form described are employedbetween the upper and lower sections to provide a cavity of desiredlength.V

3. A shielding container for radioactive material, said containercomprising a lower` section having a cavity therein closed at its lowerend but opening through the upper surface of the section, said sectionbeing provided with a centrally disposed frusto-conical projection atits upper surface surrounding said cavity, an intermediate sectionhaving a central recess of frusto-conical shape at its lower surface toreceive the frusto-conical projection on the lower section when theintermediate section is superposed thereon, said intermediate sectionhaving a centrally disposed frusto-conical projection at its uppersurface, and a central opening extending en tirely through the sectionto register with the cavity opening in the lower section, and an uppersection having a centrally disposed recess of frusto-conical shape inits lower surface to receive the frusto-conical;projection on the uppersurface of said intermediate section, the projections on the uppersurfaces of the lower and intermediate sections and the recesses in thelower surfaces of the top and intermediate sections being of the samedimensions, the upper section having a solid portion to close theopening in said intermediate section, and means for securing all of saidsections together, all of said sections being of radioactive shieldingmaterial.

References Cited in the file of this patent UNITED STATES PATENTS Browneet al Apr. 24, 1956

